1. Field of the Invention
The present invention relates to motor-driven compressors that include a motor and a compression portion for compressing a refrigerant, and more particularly, to motor-driven compressors that are suitable for use in air conditioning systems of vehicles.
2. Description of Related Art
Motor-driven compressors are driven by a power source, e.g., an external power source, such as a battery. Such motor-driven compressors including a compression portion and a motor for compressing refrigerant are known in the art. In such known motor-driven compressors, as shown in FIG. 1, an inverter 11 of a drive circuit controls the power supply to the motor, thereby controlling the rotation speed of the motor. Inverter 11 is positioned on an exterior portion of a housing 12 of the motor-driven compressor. Electric power is supplied to inverter 11 via a pair of cables 13. Each of a plurality of output terminals 14 is connected to one of a plurality of terminals 15, respectively. Each output terminal 14 is connected to a respective terminal 15 via a first wire 18. Each terminal 15 is connected to an input terminal of the motor (not shown) via a second wire 17. Moreover, inverter 11 is fixed to the exterior of housing 12 of the motor-driven compressor by a plurality of bolts 19.
In such known motor-driven compressors, a loss of power may occur at wires 17 and 18, thereby increasing the electric power consumption of the motor-driven compressor without increasing the output of the motor-driven compressor. Moreover, the number of components required for the above-described structure of drive circuits of known motor-driven compressors may increase the cost and time of manufacturing such compressors.
SUMMARY OF THE INVENTION
A need has arisen for motor-driven compressors, in which a loss of power from an electric power supply is reduced when compared with known motor-driven compressors.
A further need has arisen for motor-driven compressors with a reduced number of components when compared with known motor-driven compressors.
In an embodiment of the invention, a motor-driven compressor includes a motor and a compression portion for compressing a refrigerant. The motor-driven compressor comprises an input terminal for the motor and a drive circuit for controlling a rotation speed of the motor. The input terminal for the motor passes through an opening formed through a wall of a refrigerant suction route, whereby the input terminal is secured to the wall, and extends beyond the wall. The drive circuit controls the rotation speed of the motor and has an output connector. The output connector of the drive circuit is connected directly to the input terminal, thereby securing the drive circuit to the wall.
In a further embodiment of the invention, a motor-driven compressor comprises an input connector for a motor and a drive circuit for controlling a rotation speed of the motor. The input connector passes through an opening formed through a wall of a housing of the compressor, whereby the input connector is secured to the wall. The drive circuit controls the rotation speed of the motor and comprises an output connector that is connected to the input connector to secure the drive circuit to the wall.
In yet another embodiment of the invention, a method of assembling a motor-driven compressor comprises the steps of forming an opening through a wall of a compressor housing; passing an input terminal of a compressor motor through the opening, such that the input terminal is secured to the wall; and connecting an output terminal of a drive circuit of the motor directly to the input terminal.
Other objects, features, and advantages of this invention will be apparent to and understood by persons of ordinary skill in the art from the following description of preferred embodiments of the invention with reference to the accompanying drawings.